With the general goal of contributing to the understanding of neuronal plasticity, we have generated a model of experience-dependent plasticity in the primary auditory cortex of adult rats. Young adult rats were exposed to broad-spectrum “white” noise, calibrated at about 70 ± 10 dB SPL (decibels in sound pressure level), equivalent to the level of normal human conversation, traffic noise, audio equipment, and many workplaces in our daily lives.

Our findings indicated that the map of the auditory cortex region (tonotopic map as shown below) of the rat gets rearranged as a result of exposure to noise; the colors indicate regions that perceive highest to lowest frequencies of sound. The rearranged map in the noise-induced rats showed an entirely different pattern.

We are in process of investigating whether the altered auditory map can return to normal when the animals re-experience a normal acoustic environment. We are also interested in exploring whether the recovery can be facilitated through various training programs. Ultimately, we would like to understand correlation of the restoration of brain map with behavioral performance in recognizing and distinguishing sounds, and thus provide a scientific basis for developing new methods for hearing rehabilitation in humans. Together, these multi-level approaches to study the experience-dependent plasticity in adult animals should yield significant results that not only provide insights into theoretical neuroscience in general but also offer scientific bases for medical applications beneficial to public health.

For more information read our press release.

Download the complete Scientific Report (PDF)

back to top